I was into the truck of my 68 Z28 from LOS yesterday because I had a question about my jack from a member from this site. The jack mast is square and is 32.5 inches long and the mast is 1.125 inches square. I took a magnifying glass and found no date on the jack part even on the rivet but I found a stamp on the top of the square mast and it was a 8 B. I have no idea if this stands for February of 1968 or nothing at all. The car though is a 02E car.